Optimization And Research On The Behavior Of Truss Structures For Large-caliber Deployable Parabolic Antenna

In aerospace industry,deep space exploration requires larger space structures.Due to the limited space of vehicles,most aerospace structures need to be folded up and stored in the fairing during the launch and delivery process.After entering the designated orbit,the spacecraft is deployed and enters the working state.The expandable antenna structure has always been the most common expandable structure.Whether in the military field,or in the aerospace,information and other fields,the expandable antenna structure has a wide range of applications.On the one hand,the current application requirements increasingly demand the size of the deployable antenna structure.On the other hand,the carrying capacity of rockets is limited,and the undeployable antenna cannot meet the demand.Therefore,this paper proposes a new parabolic antenna supporting truss structure and relevant research is carried out.First,fit the working surface of the parabolic antenna structure designed in this paper.On this basis,referring to the design concept of the large-span space structure and the modular design of the existing parabolic antenna,a three-ribbed unit is proposed.Polygon grid.Establish the topology diagram model of the basic unit,and select the configuration scheme of the basic unit.To carry out geometric modeling,adopt the method of hierarchical topology and projection to establish the geometric model of the structure.Dynamic analysis is an important analysis for structural optimization design and dynamic design.Dynamic analysis of the antenna's supporting truss structure in terms of structural design,deployment control,driving,etc.is helpful to grasp the dynamic characteristics,so as to optimize the antenna structure,control the deployment process,and drive the system design for reference.After the establishment of the finite element model,the modal analysis is carried out under free mode and constrained mode,and the natural frequency and vibration mode of the structure are obtained.Modal analysis has initially verified the feasibility of the structure.On this basis,the basic rib unit of each module needs to be designed to ensure that the whole can be expanded and collapsed.Design the dimensions of the specific members of the support mechanism,and conduct kinematics research on the mechanism through analytical methods and numerical simulation.At the same time,based on the assembled antenna,a new storage rate calculation method is proposed,which greatly improves the storage efficiency of the structure.